As used herein, the following abbreviations shall have the following meanings:
AT—Answer Tones
CAMEL—Customized Applications for Mobile Network Enhanced Logic
CPC—Calling Party's Category
CRBT—Color Ringback Tone
GMSC—Gateway MSC
HLR—Home Location Register
HSS—Home Subscriber Server
ISUP—ISDN User Part
LIDB—Line Information Database
MSC—Mobile Switching Center
RBT—Ringback Tone
SCP—Service Control Point
SIP—Session Initiation Protocol
SSP—Service Switching Point
In a call made over a telecommunications system using a wireless infrastructure, wireline infrastructure or both, a calling party uses the telecommunication infrastructure to signal a called party. The party that initiates the call is referred to as the caller or calling party, and the party receiving the call is referred to as the called party or terminating party. Depending on the services provided, the calling party or called party may be the subscriber to the services.
RBT is a service wherein the called party is the subscriber. It enables the subscriber to substitute the regular audible ringing provided to a calling party with a tone or audio clip selected by the called party during the process of connecting a call. This service is also known as Color Ringback Tones (CRBT) and Answer Tones (AT). It is also possible to substitute the tone or the audio clip with other media content. Thus the RBT content presented to a caller can be video, text, graphics, photos, etc., only limited by the capabilities of the caller's handset and the transmission capabilities of the telecommunications network. RBT is a terminating service. In other words, the terminating user is the called party who subscribes to the RBT service and callers listen to RBT content as specified by the subscriber who is the called party.
With RBT, the subscriber is provided with the normal call notification while the caller is listening to the RBT content. If the subscriber answers the call, the caller is connected to the called party. Other services such as call waiting and caller identification have enriched the called party experience so as to assist the called party, here the subscriber of those services, in deciding how to handle an incoming call. There is also an enhanced version of call waiting, referred to as Call Waiting Deluxe which provides the called party with multiple choices for handling an incoming call presented as a call waiting call. However, such facility is not available when it is a first call, i.e., when the called party is idle.